1. Field of the Invention
The invention relates to a mold/chill tube having a double T-shaped inner and outer cross section in beam blank format which is encased in a water-guiding jacket adapted to its outer contour while forming a water gap.
2. Description of Related Art
In the continuous casting of metals using a chill tube, the material temperatures in the chill wall result from the heat stresses occurring during continuous casting and the cooling conditions by the respective medium, which normally, in the form of water, flows from bottom to top in a water gap between a water-guiding jacket fitted to the outer contour of the chill tube and the outer surface of the chill tube, thereby taking up the heat encountered and carrying it off. The removal of the heat with the aid of the cooling water is largely determined by the speed of the water in the water gap.
In the continuous casting of metals using a chill tube of the type in question here, it has been observed that, because of the special geometry of the beam blank format, extreme local heat stresses occur in the transition regions from middle crosspieces, which face one another head to head and are drawn in in the direction towards the longitudinal axis, and the bordering flanges which are positioned at an angle. In the case of unfavorable geometrical relationships of the transition regions, these local heat stresses lead to overheating of the chill tube, and, as a result, to a drastic reduction in its service life.